[Capt Kirk]

14" is too low. You're wanting something around 20". There's vacuum gauge reading diagnosis all over the web so look those up and pick the one that best matches what you're experiencing. Your engine looks great...is this a fresh engine or is it getting tired? With the engine idling at 850 rpm and the MP at 14" my guess is you've got a vacuum leak somewhere. I believe Skip sets the vacuum advance on the distributors he does so I wouldn't mess with it...that's not your problem.